The sad thing is that as I understand it the airlines cannot sue the ground handling agencies that cause this damage due to "indemnities"
Just to ask as a bit of an outsider on this point, I do work with construction contractors who get engaged on airport projects, and whenever working on the live side of an airfield (civil or military) it is always necessary to obtain additional "airside insurance" as the costs of damaging an aircraft are beyond the normal risks for contractors' insurances. This insurance has to cover any cause, "genuine" accidents and not. There is a story of a runaway dumper from which the driver fell and was injured, the dumper continuing driverless until it struck an RAF Tornado ! Airside would have paid up for that one.
Are handling agents somehow outside this ? Or are they regarded as "agents", to some degree under the control of their airline users, and thus the airline needs to manage their own insurance of anythng such an agent might do ?
Handling agents must still need separate insurance if they strike an aircraft on an adjacent stand from an airline who they are not agents for.